Your really fine tuning a MPFI system on a TBI hacked PCM so I'm not sure it is? But worth a shot?

The scenario you are having is in Deceleration which is a higher then idle MAP kpa which causes rich conditions and emmssions, so that's where I was thinking.

It looks to be working with commanded OL AFR just lagging a bit, in that table the amount of DE is less at lower temps.